The present invention relates to a dust sealing label strip having a plurality of dust sealing labels for sealing handle openings provided in a corrugated box for handling, and a system using the dust sealing label strip for applying the dust sealing labels over the handle openings of a corrugated box.
Corrugated boxes are known having a pair of handle openings in its opposed side walls for handling. Such handle openings are convenient for handling, but allow contaminants to enter the interior of the corrugated box. Such entrance of contaminants may, for example, cause deterioration of quality or failure of the packaged goods when the goods packaged in the corrugated box are pharmaceutical products, precision machinery, or the like.
In this regard, corrugated boxes with no handle opening are often used for packaging pharmaceutical products and the like, which results in inconvenience in handling. Alternatively, it is proposed to wrap the goods in a film before packaging in a corrugated box with handle openings. In this case, however, quite onerous operations are required in wrapping the goods in a film.
In order to overcome these troubles, for example, JP-A-62-168850 and JP-A-58-188646 propose dust protective pieces that block handle openings of a corrugated box yet allow fingers to be inserted through the openings. Such conventional dust protective pieces are discussed with reference to FIG. 8 below.
FIG. 8(a) is a plan view of a strip 80 consisting of a plurality of contiguous dust protective pieces 80a connected in series, and FIG. 8(b) is a cross sectional view taken along lines Bxe2x80x94B in FIG. 8(a).
The strip 80 is provided with perforated lines 81 along the opposed ends of each dust protective piece 80a for facilitating splitting of the strip into each dust protective piece 80a. Each dust protective piece 80a includes a cardboard 82 having an aperture 82a provided corresponding to a handle opening of a corrugated box, a film 83 laminated to the front surface of the cardboard 82 to seal the aperture 82a, and an adhesive layer 84 applied over the rear surface of the cardboard 82. The film 83 is made of a highly stretchable material such as polyurethane or latex, so that fingers may be inserted through the handle opening while the opening is blocked with the film. It is also proposed to provide a release liner over the adhesive layer 84 on the strip 80 for protecting the adhesive layer.
Before applying this dust protective piece 80a over a handle opening of a corrugated box, it is necessary to cut the strip 80 along the perforated lines 81 into pieces, apply water over the adhesive layer to give adhesiveness, and manually apply each piece to the desired location on the corrugated box. When a release liner is provided over the adhesive layer, it is also necessary before use to cut the strip 80 along the perforated lines 81 into pieces as the strip 80 is peeled from the release liner, and manually apply each piece to the desired location on the corrugated box.
In the prior art discussed above, it is required to cut the strip and, after the strip is split into single pieces, to pick and apply each single piece to the desired location on a corrugated box. Thus, in order to mechanize the process from the cutting of the strip of contiguous dust protective pieces into pieces to the application of each cut-off dust protective piece to a desired location on a corrugated box, mechanization is particularly required of the series of operations including picking up of each separated single dust protective piece and applying the same to a desired location on a corrugated box, which is quite difficult. Accordingly, such series of operations are in practice performed manually.
In spite of such difficulties, demand for corrugated boxes with such dust seals has recently been increasing, in particular in the medical industries. Development of a system is thus demanded for applying more rapidly dust protective pieces that seal handle openings of corrugated boxes and yet provide grips on the boxes, to realize mass production of corrugated boxes having dust protective pieces attached thereto in a short time.
In order to ensure sufficient strength of the handle openings of a corrugated box, the dust protective piece of the art is made of cardboard acting as a substrate to which the film is attached, as discussed above. When such dust protective pieces are attached to the outer surface of a corrugated box, the pieces may be damaged or peeled off due to abrasion between the boxes during transportation, which may also cause problems in appearance. Thus conventional dust protective pieces are usually applied to the inner surface of a corrugated box. Application of the dust protective pieces to the inner surface of a box may be easily performed manually, but cannot be mechanized readily.
It is an object of the present invention to provide a dust sealing label strip having dust sealing labels that seal a corrugated box against dust and provide grips on the box, and usable in rapid application of the sealing labels over handle openings of corrugated boxes.
It is another object of the present invention to provide a dust sealing label strip having dust sealing labels that may be applied on the outer surface of a corrugated box to seal its handle openings without being damaged or peeled off due to abrasion of the corrugated boxes during transportation, and usable in rapid application of the sealing labels over the handle openings of corrugated boxes.
It is yet another object of the present invention to provide a system for applying dust sealing labels that enables rapid application of dust sealing labels over handle openings of corrugated boxes, and realizes mass production of the corrugated boxes with the dust sealing labels in a short time.
According to the present invention, there is provided a dust sealing label strip comprising a plurality of dust sealing labels arranged on a release liner strip for application over a handle opening of a corrugated box to seal the opening, each of said dust sealing labels comprising:
a substrate having an aperture provided corresponding to a handle opening of a corrugated box,
a stretchable film laminated to said substrate to block said aperture, and
an adhesive layer,
wherein said plurality of dust sealing labels are arranged peelably via said adhesive layer on said release liner strip in at least one line at predetermined intervals.
The dust sealing label strip according to the present invention (sometimes referred to as a xe2x80x9cstrip of the present inventionxe2x80x9d hereinbelow) is characterized particularly by the peelable and adhesive arrangement of the plurality of dust sealing labels on a release liner strip in at least one line at predetermined intervals. The present strip is not a strip of a plurality of contiguous dust sealing labels that are to be cut into pieces, nor a strip of a plurality of contiguous dust sealing labels.
The present strip has the characteristic features mentioned above, so that the conventional strip-cutting step may be eliminated. Further, when the present strip is used in a system for applying dust sealing labels to be discussed later, the conventional series of manual operations including picking up of each separated single dust protective piece and applying the same to a desired location on the corrugated box, may be mechanized. Thus, the present strip enables rapid application of the dust sealing labels to handle openings of corrugated boxes and thus mass production in a short time of the corrugated boxes with the dust sealing labels applied thereon.
In the present strip, if a plurality of dust sealing labels are arranged contiguously on a release liner strip without predetermined intervals, it will be difficult, for example, to ensure peeling of a predetermined number of dust sealing labels in a suction sticker to be discussed later. Such arrangement may also cause failure to accurately position the dust sealing label on a corrugated box, following the peeling of the label from the strip, which makes it difficult to automate this series of operations.
In the present strip, it suffices if a plurality of dust sealing labels are arranged peelably in at least one line on the release liner strip at predetermined intervals. The predetermined intervals are usually regular intervals, and may suitably be selected depending on the design of the system for applying the labels. For example, the intervals may be selected from the range of 0.5 to 10 mm. The dust sealing labels are usually arranged in one line along the longitudinal axis of the strip, but may be in a plurality of lines, in particular in an even number of lines such as two lines, depending on the design of the system for applying the labels.
The strip of the present invention preferably has enough flexibility to be wound into a roll. A rolled strip occupies minimum space, so that the system for mechanizing the successive application of the dust sealing labels over the handle openings of corrugated boxes may also be in a minimum size. Such flexibility may be given to the strip by suitably selecting the material and the thickness of each layer constituting the dust sealing label.
In the present strip, it is preferred to provide, as an outermost layer of the dust sealing label arranged peelably, a layer of a material having a lower friction than that of the surfaces of the substrate and the stretchable film constituting the dust sealing label. With such a material layer having a lower friction being provided as the outermost layer, the dust sealing label may be protected from being damaged or peeled off even when the corrugated boxes having the dust sealing labels applied thereon are abraded during transportation.
The material layer may preferably be made of a material such as silicon, a nitrocellulose/polyamide-containing resin, or amixture of these.
According to the present invention, there is also provided a system for applying dust sealing labels, said system successively conveying corrugated boxes with handle openings, while successively applying dust sealing labels over the handle openings of the corrugated boxes being conveyed, said system comprising:
conveying means for successively conveying corrugated boxes with handle openings, and
application means for peeling a dust sealing label from a roll of a dust sealing label strip of claim 1, holding said label, and subsequently applying said label over a handle opening of a corrugated box conveyed by said conveying means.
With this system for applying dust sealing labels employing the dust sealing label strip of the present invention, a series of operations for applying a dust sealing label on a corrugated box having handle openings may be automated. In particular, application of dust sealing labels over the handle openings of corrugated boxes may be fully automated to achieve in a short time mass production of corrugated boxes having the dust sealing labels applied thereon.
In the present system for applying dust sealing labels, the application means may be a suction sticker for peeling and holding a dust sealing label from a dust sealing label strip by means of suction, and subsequently applying the label over a handle opening of a corrugated box conveyed by the conveying means, a suction sticker for repeatedly performing steps of peeling and holding two dust sealing labels separately from dust sealing label strips by means of suction, and applying the labels simultaneously over a pair of handle openings, respectively, of a corrugated box conveyed by said conveying means, or the like device.